Optical fibres of this kind have already been used, for a considerable period of time, instead of electrical conductors, for data transmission. The object of the light-conductor coupling means is to transmit the signals from one optical fibre to another, with minimum loss. For this purpose, it is necessary for the glass fibres to be brought as close together as possible, concenntrically and coaxially. Even the slightest relative displacement between the two optical axes results in considerable losses. The light-conductor coupling means must also protect the glass fibre connection from environmental influences such as humidity, dust, vibration and the like.
Light-conductor coupling means are already known, wherein the two optical fibres, which are each mounted in a respective end member, are held together by means of a cylindrical metal sleeve. A coupling means of this kind is described for example in German DAS No 23 52 874. In Order to ensure that the two optical fibres are centered absolutely without play in the centering sleeve, the end members and the centering sleeve must be machined to extremely fine tolerances. However, this means that when the two end members are pushed together in the centering sleeve, the air which is enclosed therein finds it virtually impossible to escape. This results in the formation between the two end members of a resilient air cushion which, in extreme cases, prevents the two optical fibres from lying against each other. Boring holes in the casing of the centering sleeve is not a practical solution, as dust and dirt could penetrate through such openings to the light fibres. In addition, bores of this kind give rise to fine accumulations which can no longer be removed from the interior of the centering sleeve and which can be the cause of the optical axes of the optical fibres suffering from slight displacement.